View Compilation Error

0_0_37781784_9700.cpp:114:24: error: 'solve' function uses 'auto' type specifier without trailing return type
 auto solve(int n, int m) {
                        ^
0_0_37781784_9700.cpp:114:24: note: deduced return type only available with -std=c++1y or -std=gnu++1y